Fahr’s disease is bilateral, symmetric, and idiopathic calcifications in basal ganglia. Calcification is one of the three basic features. The others are psychiatric symptoms and movement disorders. Psychiatric symptoms are mood changes, psychosis, obsessions, and personality changes. These symptoms appear not only with neurological symptoms but also are rarely isolated. Cummings and friends described two types of Fahr’s disease. Presentation with psychosis is “early-onset type” and typically manifested dementia with motor system disorders is called “late-onset type”. In this case report, we discussed a case that had begun with obsession followed by manic episode with psychotic symptoms, that is considered to be of organic etiology because of its atypical psychiatric clinical appearance, diagnosed as Fahr’s disease as a result of neuroimaging techniques and further investigations. We think that this case will contribute to literature about psychiatric aspects of basal ganglia and approach to the psychiatric patients.